提高双砜S产率的合成方法研究

Synthesis of 4,4′ Dihydroxydiphenyl Sulfone

以苯酚和硫酸为原料 ,采用分段真空脱水及添加适量苯酚的方法合成双砜S。其结果表明 ,苯酚添加量是影响双砜S产率的关键。最佳反应条件为 :苯酚与浓硫酸的物质的量比为1 0 0 0∶1 175 ,反应温度 10 0℃ ,反应时间 3h ;然后提高温度至 145～ 15 0℃ ,每反应 1h抽真空 (残压 :0 0 3～ 0 .0 4MPa) 15min ,共抽 3次 ;每次抽完真空后 ,添加适量苯酚 ,总共加入第一次用量的1 12 5倍 ,4h后反应结束 ,双砜S产率达到 82 %。

A new method for synthesizing 4,4′ dihydroxydiphenyl sulfone(Ⅰ) from phenol and sulfuric acid was studied,in which stepwise vacuum dehydration was adopted with supplementary addition of phenol.It was found that quantity of phenol added during the reaction was the key factor influencing the rate of production.The optimum conditions were as follows.Phenol and sulfuric acid(at mole ratio 1 000∶1 175) reacted at 100 ℃ for 3 h(sulfonation of phenol).Then the temperature was raised to 150 ℃ and reaction was continued for 4 h during which water was removed at 0 03～0 04 MPa for 15 min after each hour of reaction(3 times totally).112.5% phenol based on original offer was divided equally into three dosages and added separately after each time of dehydration.The yield of Ⅰ reached 82%.